Commit Graph

12 Commits

Author SHA1 Message Date
Marcel Moolenaar
f2c49dd248 Revamp of the syscall path, exception and context handling. The
prime objectives are:
o  Implement a syscall path based on the epc inststruction (see
   sys/ia64/ia64/syscall.s).
o  Revisit the places were we need to save and restore registers
   and define those contexts in terms of the register sets (see
   sys/ia64/include/_regset.h).

Secundairy objectives:
o  Remove the requirement to use contigmalloc for kernel stacks.
o  Better handling of the high FP registers for SMP systems.
o  Switch to the new cpu_switch() and cpu_throw() semantics.
o  Add a good unwinder to reconstruct contexts for the rare
   cases we need to (see sys/contrib/ia64/libuwx)

Many files are affected by this change. Functionally it boils
down to:
o  The EPC syscall doesn't preserve registers it does not need
   to preserve and places the arguments differently on the stack.
   This affects libc and truss.
o  The address of the kernel page directory (kptdir) had to
   be unstaticized for use by the nested TLB fault handler.
   The name has been changed to ia64_kptdir to avoid conflicts.
   The renaming affects libkvm.
o  The trapframe only contains the special registers and the
   scratch registers. For syscalls using the EPC syscall path
   no scratch registers are saved. This affects all places where
   the trapframe is accessed. Most notably the unaligned access
   handler, the signal delivery code and the debugger.
o  Context switching only partly saves the special registers
   and the preserved registers. This affects cpu_switch() and
   triggered the move to the new semantics, which additionally
   affects cpu_throw().
o  The high FP registers are either in the PCB or on some
   CPU. context switching for them is done lazily. This affects
   trap().
o  The mcontext has room for all registers, but not all of them
   have to be defined in all cases. This mostly affects signal
   delivery code now. The *context syscalls are as of yet still
   unimplemented.

Many details went into the removal of the requirement to use
contigmalloc for kernel stacks. The details are mostly CPU
specific and limited to exception_save() and exception_restore().
The few places where we create, destroy or switch stacks were
mostly simplified by not having to construct physical addresses
and additionally saving the virtual addresses for later use.

Besides more efficient context saving and restoring, which of
course yields a noticable speedup, this also fixes the dreaded
SMP bootup problem as a side-effect. The details of which are
still not fully understood.

This change includes all the necessary backward compatibility
code to have it handle older userland binaries that use the
break instruction for syscalls. Support for break-based syscalls
has been pessimized in favor of a clean implementation. Due to
the overall better performance of the kernel, this will still
be notived as an improvement if it's noticed at all.

Approved by: re@ (jhb)
2003-05-16 21:26:42 +00:00
Peter Wemm
23eeeff7be Split 4.x and 5.x signal handling so that we can keep 4.x signal
handling clean and functional as 5.x evolves.  This allows some of the
nasty bandaids in the 5.x codepaths to be unwound.

Encapsulate 4.x signal handling under COMPAT_FREEBSD4 (there is an
anti-foot-shooting measure in place, 5.x folks need this for a while) and
finish encapsulating the older stuff under COMPAT_43.  Since the ancient
stuff is required on alpha (longjmp(3) passes a 'struct osigcontext *'
to the current sigreturn(2), instead of the 'ucontext_t *' that sigreturn
is supposed to take), add a compile time check to prevent foot shooting
there too.  Add uniform COMPAT_43 stubs for ia64/sparc64/powerpc.

Tested on: i386, alpha, ia64.  Compiled on sparc64 (a few days ago).
Approved by: re
2002-10-25 19:10:58 +00:00
Mike Barcroft
795b630655 struct ia64_fpreg needs to be available outside of the kernel for
struct sigcontext.

Pointy hat to: mike
2002-10-13 15:30:17 +00:00
Mike Barcroft
7a77412855 Add standards visibility conditionals. Change any uses of sigset_t to
struct __sigset to avoid depending on objects from <sys/signal.h>.
2002-10-13 00:31:46 +00:00
Peter Wemm
c692fbe091 At great personal risk, add a __packed and __aligned(x) define that
expand to __attribute__((packed)) and __attribute__((aligned(x)))
respectively.  Replace the handful of gcc-ism's that use
__attribute__((aligned(16))) etc around the kernel with __aligned(16).

There are over 400 __attribute__((packed)) to deal with, that can come
later.  I just want to use __packed in new code rather than add more
gcc-ism's.
2002-09-23 05:55:10 +00:00
Peter Wemm
b11ac5597c Make this compile 2002-09-03 04:30:00 +00:00
Doug Rabson
4fc38782f0 Add ucode values for SIGFPE etc. Copied from i386/include/signal.h. 2002-04-10 19:24:08 +00:00
David E. O'Brien
1792335469 style(9) the structure definitions. 2001-09-05 01:36:46 +00:00
Marcel Moolenaar
806d7daafe Make MINSIGSTKSZ machine dependent, and have the sigaltstack
syscall compare against a variable sv_minsigstksz in struct
sysentvec as to properly take the size of the machine- and
ABI dependent struct sigframe into account.

The SVR4 and iBCS2 modules continue to have a minsigstksz of
8192 to preserve behavior. The real values (if different) are
not known at this time. Other ABI modules use the real
values.

The native MINSIGSTKSZ is now defined as follows:

Arch		MINSIGSTKSZ
----		-----------
alpha		    4096
i386		    2048
ia64		   12288

Reviewed by: mjacob
Suggested by: bde
2000-11-09 08:25:48 +00:00
Doug Rabson
ce97a5fc4e * Various fixes to breakage introduced by the atomic and mutex reorgs.
* Fixes to the signal delivery code. Not quite right yet.

I would have preferred to wait until I have signal delivery actually
working but the current kernel in CVS doesn't build.
2000-10-24 19:54:38 +00:00
Doug Rabson
8d9761debf Next round of fixes to the ia64 code. This includes simulated clock and
disk drivers along with a load of fixes to context switching, fork
handling and a load of other stuff I can't remember now. This takes us as
far as start_init() before it dies. I guess now I will have to finish off
the VM system and syscall handling :-).
2000-10-04 17:53:03 +00:00
Doug Rabson
1ebcad5720 This is the first snapshot of the FreeBSD/ia64 kernel. This kernel will
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.
2000-09-29 13:46:07 +00:00